asp gridView 无数据时候，显示表头

 public void Gridview_BindNoRecords(GridView gridView, DataTable dt) // gridView，绑定数据源DT
    {
        int a = dt.Rows.Count;
        if (dt.Rows.Count == 0)
        {
            dt.Rows.Add(dt.NewRow());
            gridView.DataSource = dt;
            gridView.DataBind();
            int columnCount = gridView.Rows[0].Cells.Count;
            gridView.Rows[0].Cells.Clear();
            gridView.Rows[0].Cells.Add(new TableCell());
            gridView.Rows[0].Cells[0].ColumnSpan = columnCount;
            gridView.Rows[0].Cells[0].Text = "要显示的内容";
            gridView.RowStyle.HorizontalAlign = System.Web.UI.WebControls.HorizontalAlign.Center;
        }
    }
调用：
在 gridView.BindData();方法后 调用！